An emergency operation will get under way today to transport massive amounts of drinking water to Inis Meain, the middle of the three Aran Islands, after reservoir levels on the island fell to drastically low levels.

Water on the neighbouring isle of Inis Oirr is also running low and a decision on ferrying water there is dependent on whether there is enough rain falls over the next few weeks.

The limestone terrain of the islands makes it difficult for rainwater to be retained for use and much of it seeps away, causing annual shortages.

The recent fine weather has led to water restrictions on both Inis Meain and Inis Oirr in June and July; however, there are no water problems on Inis Mor. Most recently, Galway County Council imposed daily restrictions from 10am to 6pm and from 8am to 8pm respectively in an attempt to retain sufficient supplies.

The council said it regretted taking the measure, but there was "no other option at present to ensure a supply remains available".

The continuing sunny weather has forced the council's hand and, in conjunction with Irish Water, emergency supplies were being ferried from the port of Rossaveal to Inis Meain yesterday.

On average, 50,000 gallons a day will be transported to the island by the cargo ferry company Lasta Mara Teo.

The water shortage could not have come at a worse time for Inis Meain. The island is packed with holidaymakers, but tourism businesses are struggling to provide the basic water-based necessities.

The Inis Meain Restaurant took matters into its own hands a couple of years ago, when it splashed out on its own tank and processing facility to ensure it could properly cater for its customers.

"It is a huge problem on the island and we had to close our business for a couple of days when we installed our own tank," said a restaurant spokesperson. "It is peak season for us and we are very busy. If water was to be rationed further it would be a problem for everyone," he said.

Irish Water said that, along with the council, it was finalising plans for the replenishment of the water supply to the reservoir reserves but there were "sufficient" resources.